gdb/gdbserver/utils.c

   1 /* General utility routines for the remote server for GDB.
   2    Copyright (C) 1986, 1989, 1993, 1995, 1996, 1997, 1999, 2000, 2002, 2003,
   3    2007, 2008, 2009, 2010 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "server.h"
  21 #include <stdio.h>
  22 #include <string.h>
  23 #include <stdlib.h>
  24 #if HAVE_ERRNO_H
  25 #include <errno.h>
  26 #endif
  27 #if HAVE_MALLOC_H
  28 #include <malloc.h>
  29 #endif
  30
  31 /* Generally useful subroutines used throughout the program.  */
  32
  33 static void malloc_failure (size_t size) ATTR_NORETURN;
  34
  35 static void
  36 malloc_failure (size_t size)
  37 {
  38   fprintf (stderr, "gdbserver: ran out of memory while trying to allocate %lu bytes\n",
  39            (unsigned long) size);
  40   exit (1);
  41 }
  42
  43 /* Allocate memory without fail.
  44    If malloc fails, this will print a message to stderr and exit.  */
  45
  46 void *
  47 xmalloc (size_t size)
  48 {
  49   void *newmem;
  50
  51   if (size == 0)
  52     size = 1;
  53   newmem = malloc (size);
  54   if (!newmem)
  55     malloc_failure (size);
  56
  57   return newmem;
  58 }
  59
  60 /* Reallocate memory without fail.  This works like xmalloc. */
  61
  62 void *
  63 xrealloc (void *ptr, size_t size)
  64 {
  65   void *val;
  66
  67   if (size == 0)
  68     size = 1;
  69
  70   if (ptr != NULL)
  71     val = realloc (ptr, size);  /* OK: realloc */
  72   else
  73     val = malloc (size);        /* OK: malloc */
  74   if (val == NULL)
  75     malloc_failure (size);
  76
  77   return val;
  78 }
  79
  80 /* Allocate memory without fail and set it to zero.
  81    If malloc fails, this will print a message to stderr and exit.  */
  82
  83 void *
  84 xcalloc (size_t nelem, size_t elsize)
  85 {
  86   void *newmem;
  87
  88   if (nelem == 0 || elsize == 0)
  89     nelem = elsize = 1;
  90
  91   newmem = calloc (nelem, elsize);
  92   if (!newmem)
  93     malloc_failure (nelem * elsize);
  94
  95   return newmem;
  96 }
  97
  98 /* Copy a string into a memory buffer.
  99    If malloc fails, this will print a message to stderr and exit.  */
 100
 101 char *
 102 xstrdup (const char *s)
 103 {
 104   char *ret = strdup (s);
 105   if (ret == NULL)
 106     malloc_failure (strlen (s) + 1);
 107   return ret;
 108 }
 109
 110 /* Free a standard argv vector.  */
 111
 112 void
 113 freeargv (char **vector)
 114 {
 115   char **scan;
 116
 117   if (vector != NULL)
 118     {
 119       for (scan = vector; *scan != NULL; scan++)
 120         {
 121           free (*scan);
 122         }
 123       free (vector);
 124     }
 125 }
 126
 127 /* Print the system error message for errno, and also mention STRING
 128    as the file name for which the error was encountered.
 129    Then return to command level.  */
 130
 131 void
 132 perror_with_name (const char *string)
 133 {
 134   const char *err;
 135   char *combined;
 136
 137   err = strerror (errno);
 138   if (err == NULL)
 139     err = "unknown error";
 140
 141   combined = (char *) alloca (strlen (err) + strlen (string) + 3);
 142   strcpy (combined, string);
 143   strcat (combined, ": ");
 144   strcat (combined, err);
 145
 146   error ("%s.", combined);
 147 }
 148
 149 /* Print an error message and return to command level.
 150    STRING is the error message, used as a fprintf string,
 151    and ARG is passed as an argument to it.  */
 152
 153 void
 154 error (const char *string,...)
 155 {
 156   extern jmp_buf toplevel;
 157   va_list args;
 158   va_start (args, string);
 159   fflush (stdout);
 160   vfprintf (stderr, string, args);
 161   fprintf (stderr, "\n");
 162   longjmp (toplevel, 1);
 163 }
 164
 165 /* Print an error message and exit reporting failure.
 166    This is for a error that we cannot continue from.
 167    STRING and ARG are passed to fprintf.  */
 168
 169 /* VARARGS */
 170 void
 171 fatal (const char *string,...)
 172 {
 173   va_list args;
 174   va_start (args, string);
 175   fprintf (stderr, "gdbserver: ");
 176   vfprintf (stderr, string, args);
 177   fprintf (stderr, "\n");
 178   va_end (args);
 179   exit (1);
 180 }
 181
 182 /* VARARGS */
 183 void
 184 warning (const char *string,...)
 185 {
 186   va_list args;
 187   va_start (args, string);
 188   fprintf (stderr, "gdbserver: ");
 189   vfprintf (stderr, string, args);
 190   fprintf (stderr, "\n");
 191   va_end (args);
 192 }
 193
 194 /* Report a problem internal to GDBserver, and exit.  */
 195
 196 void
 197 internal_error (const char *file, int line, const char *fmt, ...)
 198 {
 199   va_list args;
 200   va_start (args, fmt);
 201
 202   fprintf (stderr,  "\
 203 %s:%d: A problem internal to GDBserver has been detected.\n", file, line);
 204   vfprintf (stderr, fmt, args);
 205   fprintf (stderr, "\n");
 206   va_end (args);
 207   exit (1);
 208 }
 209
 210 /* Temporary storage using circular buffer.  */
 211 #define NUMCELLS 4
 212 #define CELLSIZE 50
 213
 214 /* Return the next entry in the circular buffer.  */
 215
 216 static char *
 217 get_cell (void)
 218 {
 219   static char buf[NUMCELLS][CELLSIZE];
 220   static int cell = 0;
 221   if (++cell >= NUMCELLS)
 222     cell = 0;
 223   return buf[cell];
 224 }
 225
 226 /* Stdarg wrapper around vsnprintf.
 227    SIZE is the size of the buffer pointed to by STR.  */
 228
 229 static int
 230 xsnprintf (char *str, size_t size, const char *format, ...)
 231 {
 232   va_list args;
 233   int ret;
 234
 235   va_start (args, format);
 236   ret = vsnprintf (str, size, format, args);
 237   va_end (args);
 238
 239   return ret;
 240 }
 241
 242 /* Convert a CORE_ADDR into a HEX string, like %lx.
 243    The result is stored in a circular static buffer, NUMCELLS deep.  */
 244
 245 char *
 246 paddress (CORE_ADDR addr)
 247 {
 248   char *str = get_cell ();
 249   xsnprintf (str, CELLSIZE, "%lx", (long) addr);
 250   return str;
 251 }
 252
 253 static char *
 254 decimal2str (char *sign, ULONGEST addr, int width)
 255 {
 256   /* Steal code from valprint.c:print_decimal().  Should this worry
 257      about the real size of addr as the above does? */
 258   unsigned long temp[3];
 259   char *str = get_cell ();
 260
 261   int i = 0;
 262   do
 263     {
 264       temp[i] = addr % (1000 * 1000 * 1000);
 265       addr /= (1000 * 1000 * 1000);
 266       i++;
 267       width -= 9;
 268     }
 269   while (addr != 0 && i < (sizeof (temp) / sizeof (temp[0])));
 270
 271   width = 9;
 272   if (width < 0)
 273     width = 0;
 274
 275   switch (i)
 276     {
 277     case 1:
 278       xsnprintf (str, CELLSIZE, "%s%0*lu", sign, width, temp[0]);
 279       break;
 280     case 2:
 281       xsnprintf (str, CELLSIZE, "%s%0*lu%09lu", sign, width,
 282                  temp[1], temp[0]);
 283       break;
 284     case 3:
 285       xsnprintf (str, CELLSIZE, "%s%0*lu%09lu%09lu", sign, width,
 286                  temp[2], temp[1], temp[0]);
 287       break;
 288     default:
 289       internal_error (__FILE__, __LINE__,
 290                       "failed internal consistency check");
 291     }
 292
 293   return str;
 294 }
 295
 296 /* %u for ULONGEST.  The result is stored in a circular static buffer,
 297    NUMCELLS deep.  */
 298
 299 char *
 300 pulongest (ULONGEST u)
 301 {
 302   return decimal2str ("", u, 0);
 303 }
 304
 305 /* %d for LONGEST.  The result is stored in a circular static buffer,
 306    NUMCELLS deep.  */
 307
 308 char *
 309 plongest (LONGEST l)
 310 {
 311   if (l < 0)
 312     return decimal2str ("-", -l, 0);
 313   else
 314     return decimal2str ("", l, 0);
 315 }
 316
 317 /* Eliminate warning from compiler on 32-bit systems.  */
 318 static int thirty_two = 32;
 319
 320 /* Convert a ULONGEST into a HEX string, like %lx.  The result is
 321    stored in a circular static buffer, NUMCELLS deep.  */
 322
 323 char *
 324 phex_nz (ULONGEST l, int sizeof_l)
 325 {
 326   char *str;
 327
 328   switch (sizeof_l)
 329     {
 330     case 8:
 331       {
 332         unsigned long high = (unsigned long) (l >> thirty_two);
 333         str = get_cell ();
 334         if (high == 0)
 335           xsnprintf (str, CELLSIZE, "%lx",
 336                      (unsigned long) (l & 0xffffffff));
 337         else
 338           xsnprintf (str, CELLSIZE, "%lx%08lx", high,
 339                      (unsigned long) (l & 0xffffffff));
 340         break;
 341       }
 342     case 4:
 343       str = get_cell ();
 344       xsnprintf (str, CELLSIZE, "%lx", (unsigned long) l);
 345       break;
 346     case 2:
 347       str = get_cell ();
 348       xsnprintf (str, CELLSIZE, "%x", (unsigned short) (l & 0xffff));
 349       break;
 350     default:
 351       str = phex_nz (l, sizeof (l));
 352       break;
 353     }
 354
 355   return str;
 356 }